基于超声波测试的片岩单轴抗压强度预测模型

Prediction model of schist uniaxial compressive strength based on ultrasonic tests

岩石单轴抗压强度是岩土工程中最基础、最重要的参数之一,建立其快速、方便、经济的预测方法一直是岩土界的研究热点。为了获取片岩单轴抗压强度的预测模型,基于超声波试验和单轴压缩试验数据,对福建某矿山的片岩岩样分别开展了单轴抗压强度与纵波波速、横波波速、纵波模量、横波模量、动弹性模量和静弹性模量的回归性分析,并各自建立了线性、对数、多项式、指数函数和幂函数5种回归模型。分析表明,除了动弹性模量以外,其他参量都易受空间变异性和各向异性影响,不适合用于片岩单轴抗压强度的预测。最终,通过拟合度、所包含参量、量纲平衡、测试方法以及显著性分析,确定基于动弹性模量建立的线性回归模型是最合理、可靠、方便的片岩单轴抗压强度预测模型。研究成果可为开展岩石单轴抗压强度预测的相关理论研究和工程应用提供参考和帮助。

Uniaxial compressive strength of rock is one of the most basic and important parameters in geotechnical engineering.It has become a research hotspot in geotechnical field to establish a fast,convenient and economic prediction method.In order to obtain the prediction model of the schist uniaxial compressive strength,the regression analyses of uniaxial compressive strength with P-wave velocity,S-wave velocity,P-wave modulus,S-wave modulus,dynamic elastic modulus and static elastic modulus are carried out based on the data of ultrasonic test and uniaxial compression test for schist samples of collected in a mine in Fujian Province.Five regression models of linear,logarithmic,polynomial,exponential and power functions are established respectively.The results show that all other parameters,except dynamic modulus of elasticity,are not suitable for predicting the uniaxial compressive strength of the schist due to the influences of spatial variability and anisotropy.Finally,the linear regression model based on the dynamic modulus of elasticity is determined to be the most reasonable,reliable and convenient prediction model of the schist uniaxial compressive strength based on the fitting degree,connotation parameter,dimensional balance,testing method and significance analysis.The results can provide reference and help for the relevant theoretical research and engineering application.